Mystery Black Covering on Whirlpool Dishwasher
Our 2015 Whirlpool Gold Series dishwasher is covered in a dark residue on the inside unit walls and door. The dishes come out "clean", but the rust colored film occurs with every wash. We have run vinegar loads, super hot cycles with no dishes, checked the electric, checked the drains, cleaned the filter changed detergents. All to no avail. Any ideas? Note that if you wipe the inside of the dishwasher with a paper towel the towel will quickly turn brown/black with the residue. Do another load and it comes back. Any ideas what the residue is or how to end it? We are just outside of Chicago and have Lake Michigan water. Thanks!